[Valhi, Inc. Letterhead]

Steven L. Watson
President
(972) 450-4216

                               September 19, 2001

Board of Directors                                       Board of Directors
Titanium Metals Corporation                              Tremont Corporation
1999 Broadway                                            1999 Broadway
Suite 4300                                               Suite 4300
Denver, Colorado  80202                                  Denver, Colorado  80202

Ladies and Gentlemen:

     Valhi,  Inc. and Tremont  Corporation own 30,135,390  shares and 10,215,541
shares,  respectively,  of the common stock of NL Industries, Inc., representing
approximately 81.5% of the outstanding shares of NL.

     Valhi  believes  TIMET's  acquisition  of the NL  shares  held by Valhi and
Tremont in a  transaction  in which each NL share would be exchanged for 1.65 to
2.00 shares of newly-issued TIMET common stock plus TIMET debt securities in the
principal amount of $10.00 to $12.00, with terms to be appropriately determined,
would  provide  an  attractive  investment  opportunity  for TIMET at a fair and
reasonable price for all parties. Such an acquisition would, among other things,
(i) allow TIMET to diversify into an industry that  historically  would moderate
TIMET's  business  cycles,  (ii) provide a significant  and consistent  level of
profitability to offset TIMET's  inconsistent  financial results,  (iii) improve
access to capital  resources and markets as a result of a  significantly  larger
asset and capital  base,  (iv)  facilitate  future growth  through  expansion of
current operations and potential acquisitions,  (v) provide for opportunities to
achieve  administrative  cost  savings  and (vi) result in TIMET and NL becoming
members of the same consolidated tax group, which could provide  significant tax
benefits to TIMET.

     Your prompt consideration and response to this proposal is appreciated.

                                                     Sincerely,



                                                     Steven L. Watson, President